The present disclosure relates to a communication apparatus and a communication method for operating as a source device simultaneously transmitting data to a plurality of sync devices that reproduce data, to a communication apparatus and a communication method for operating as a sync device that receives data transmitted from a source device and carries out a reproduction process, and to a communication system composed of one source device and a plurality of sync devices. In particular, the present disclosure relates to a communication apparatus and a communication method for operating as a source device and transmitting data to a plurality of sync devices that have been subjected to a pairing process, to a communication apparatus and a communication method for carrying out a pairing process with other sync devices and receiving and reproducing data transmitted from a source device, and to a communication system composed of one source device and a plurality of sync devices subjected to a pairing process.
Due to the spread of communication technology, data can now be transferred between devices such as personal computers (PCs) or the like using a wireless network such as a wireless LAN (Local Area Network). For wireless LAN technology, the main standards are IEEE 801.11 and the Wi-Fi Alliance. The technical specification of a wireless LAN is standardized according to IEEE802.11 and the Wi-Fi Alliance sets the method of testing for interoperability and certifies products.
Wireless LAN technology can be used in various applications. As one example, it is possible to use wireless LAN technology when video data and audio data are transmitted from one source device, such as a personal computer or a tuner device, respectively to two sync devices in the form of a video reproduction sync device (such as a TV set) with a video reproduction function and an audio reproduction sync device (such as a speaker) with an audio reproduction function.
Various applications of this technology have already been proposed. Japanese Laid-Open Patent Publication No. 2010-166481 discloses a sync device capable of determining, when reproducing AV (audio-video) data transferred wirelessly according to wireless multicast transmission from a source device, the wireless connection state of other sync devices that reproduce AV data from the same source device. Japanese Laid-Open Patent Publication No. 2010-166609 discloses a source device capable of transmitting, when AV data transferred wirelessly from the source device according to wireless multicast transmission is reproduced, sync device information on each sync device to enable the respective sync devices to determine the wireless connection states of the other sync devices that reproduce AV data from the same source device. Japanese Laid-Open Patent Publication Nos. 2010-166610 and 2010-166611 disclose a source device capable of transmitting, when AV data transferred wirelessly from the source device according to wireless multicast transmission is reproduced, sync device information to enable the respective sync devices to determine the wireless connection states of the other sync devices that reproduce AV data from the same source device. Japanese Laid-Open Patent Publication No. 2010-166612 discloses a sync device capable of determining, when AV data transferred wirelessly from a source device according to wireless multicast transmission is reproduced, the wireless connection state of other sync devices that reproduce AV data from the same source device and also a source device that transmits AV data to such sync device.
In a communication system composed of a source device that transmits AV data, a video reproduction sync device, and an audio reproduction sync device as described above, once the video reproduction sync device and the audio reproduction sync device have been subjected to a pairing process, during subsequent connecting operations, by merely selecting the video reproduction sync device, it is possible to have the corresponding audio reproduction sync device automatically selected. By doing so, in a case where the communication system is frequently used, it is possible to reduce the burden placed on the user. Normally, the pairing process for pairing sync devices together is carried out by the user operating the video reproduction sync device and the audio reproduction sync device.
To use a connection scheme with a source device that transmits AV data and a video reproduction sync device and an audio reproduction sync device, it is normally necessary for the user to carry out the operation described below, which is troublesome for the user.                (1) The user operates both the video reproduction sync device and the audio reproduction sync device to perform a pairing process for the two devices.        (2) The user operates both the source device and the video reproduction sync device to connect such devices.        (3) The user operates both the source device and the audio reproduction sync device to connect such devices.        